With or without hold?
For just a plain protectant, Tigi/Catwalk makes a good one that doesn't leave much of a product-y feeling afterwards. Wella's Eimi styling line also has a decent one. My favorite stylers are from the Colorproof line (everything from them has heat protection), but it can be a hard brand to find + expensive.
If you're looking for something with a good hold, especially if you have fine hair that hates holding curls, I suggest Redken's #22 Hot Sets>>176738
Try Olaplex. If you can get the #1 and #2 treatments from a stylist and then get the Take Home #3, it should help significantly.